In such a device for the selectively controlled mutual displacement of yarn guides of flat-bed knitting machines of this type, known from German DE 36 06 821 A1 or Swiss CH 655 145 A5, the electromagnet is connected to the mutual displacement or take-along finger by means of a lever mechanism. In the first case the mutual displacement finger is activated by a parallel tension spring and provided with a bolt extending away from it. The mutual displacement finger is seated in a one-armed lever, which is pre-stressed by a further tension spring and can be activated by the electromagnet for unlocking the mutual displacement finger. In the second case a two-armed lever is provided, one end of which is activated by a spring-loaded armature rod of the electromagnet and the other end of which is connected with the mutual displacement finger for moving the latter up and down.
A disadvantage of both known devices is that the transfer of the motion from the electromagnet to the mutual displacement finger is relatively sluggish because of the lever-like transfer elements. This is inherent because of the masses to be moved, on the one hand, and because of the plurality of the elements transferring the motion, on the other. A further disadvantage is the asymmetrical location of the electromagnets in relation to the mutual displacement finger, which results in an uneven distribution of forces at the mutual displacement finger, which depends on the direction of motion at the mutual displacement finger and the maximally appearing force of which must be provided by the electromagnet. This results in a control- or operating time of the mutual displacement finger, which is dependent on the operational state at the time in, which is unsatisfactory.
Although in a device for the selectively controlled mutual displacement of yarn guides of flat-bed knitting machines, known from East German DD-227 465 A, the mutual displacement finger arrangement consisting of two parallel mutual displacement fingers is fastened on one end of an armature rod of the electromagnet, because of the axial arrangement of the armature rod and the mutual displacement finger arrangement a guide section located between them is required for the axial movement of the mutual displacement finger arrangement. This increases the structural height of this device. Therefore the device in accordance with the above mentioned German DE 36 02 821 A1 was used again, where the electromagnet and the mutual displacement finger are disposed parallel to each other, which has the disadvantages mentioned above.